Phen From Ireland, joined Oct 2007, 294 posts, RR: 0 Posted (3 years 6 months 1 week 2 days 17 hours ago) and read 4811 times:
On watching this video http://www.youtube.com/watch?v=dijpw392JU0, I was surprised to hear that only the main left cabin door is motorized on QF 767s. Is this true for all Boeing 767s? How heavy are the other doors to lift manually?
Mir From United States of America, joined Jan 2004, 19716 posts, RR: 56 Reply 2, posted (3 years 6 months 1 week 2 days 16 hours ago) and read 4784 times:
Quoting Phen (Thread starter): How heavy are the other doors to lift manually?
The doors are going to be pretty heavy, but they should have some sort of mechanical assist, like a set of springs that help pull the door up.
BTW, the guy in that video sounds like he should be recording movie trailers.
-Mir
7 billion, one nation, imagination...it's a beautiful day
474218 From United States of America, joined Oct 2005, 6340 posts, RR: 10 Reply 3, posted (3 years 6 months 1 week 2 days 16 hours ago) and read 4773 times:
The 767 (and DC-10, MD-11 and L-1011) passenger doors are electrically operated up and down, and work against a counter balance that is strong enough to open the door and deploy the slides in an emergency.
Mender From United Kingdom, joined Feb 2004, 224 posts, RR: 0 Reply 4, posted (3 years 6 months 1 week 2 days 15 hours ago) and read 4744 times:
I've not watched the video as it wouldn't open for some reason. However I've seen electrically operated doors L1 and L2 doors on the 767. The doors are counterbalanced so they are fairly easy to open with or without electrical assistance if they are correctly rigged.
Quoting 474218 (Reply 3): and work against a counter balance that is strong enough to open the door and deploy the slides in an emergency.
If you open a door with the slide armed, the weight of the slide is effectivly detached from the door. Therefore the counterbalance pull the door upwards so strongly that you would not be able to hold it down/closed
474218 From United States of America, joined Oct 2005, 6340 posts, RR: 10 Reply 5, posted (3 years 6 months 1 week 2 days 15 hours ago) and read 4731 times:
Quoting Mender (Reply 4): If you open a door with the slide armed, the weight of the slide is effectivly detached from the door. Therefore the counterbalance pull the door upwards so strongly that you would not be able to hold it down/closed
I have no idea what you are trying to say. But like I said, in normal operation, when the door is shut electrically it loads the counter balance so the door can be opened in an emergency and deploy the slide. When the door is opened the electric motor actually holds the door back against the counter balance.
N901WA From United States of America, joined Oct 2009, 385 posts, RR: 0 Reply 6, posted (3 years 6 months 1 week 2 days 15 hours ago) and read 4712 times:
Hi, I hope this can help. Yes on all the 767 I have worked on (Delta, Hawaiian, Qantas, Citybird, Aeroflot and Martin Air) the Foward left and sometimes the Left fwd 2 Main Cabin doors has a Electric Motor driven door. On Delta's 767 with 4 Main Cabin doors they are set up that way. On the 767 with 6 Main Cabin doors the 2 Fwd Main Cabin Doors on the Left side have Electric drives.
The doors all have a Counterbalance system but the other doors are all manual lift. When you lift the open handle the Counterbalance system opens the doors about half way up and you have to manualy have to lift them from there. When closing the Manual doors (1R 2L & R or 1R , 2R and 3L & R) you have to push the hold open latch and pull the door down till the latch system picks up the door to latch it closed. On the Electric driven doors the drives takes it down to the same point to pick up the latch system.
On the L1011 , MD-11 and DC10 all the main doors were driven all the way closed and open.
I little extra info, on the 767's with 3 Main Cabin doors and 2 Med sized doors aft of the Trailing edge are simple plug doors and only for emergencys like the overwing doors on other 767's. I hope this all makes sense Darren
Tdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80 Reply 7, posted (3 years 6 months 1 week 2 days 14 hours ago) and read 4702 times:
Quoting 474218 (Reply 5):
I have no idea what you are trying to say.
Mender is noting that when you open a door with the slide armed, the slide is now attached to the door frame, not the door.
As a result, a counterweight that can lift the door open in normal configuration (door + slide) will give you a much higher net force when you're opening the door with the slide armed (weight of the door only).
Mender From United Kingdom, joined Feb 2004, 224 posts, RR: 0 Reply 8, posted (3 years 6 months 1 week 2 days 14 hours ago) and read 4690 times:
I'm not disagreeing with you, I'm trying to make it a little clearer people to understand who haven't used a 767 door.
Clearly I've failed so I'll try to be even clearer.
With a door that HASN'T got electric assist the weight of the door is roughly balance by the counterbalance, in fact the door will gently rise up merely by unlatching it.
In fact, it is harder to close a 767 door than it is to open it because of the counterbalance is pulling the door up against you trying to close it. It's not a big upward pull but it's enough.
When the door is opened to deploy the slide, the slide detaches from the door almost straight away as it is attached to the floor by the girt bar. Because the door is now a lot lighter (without the slide) the counterbalance yanks the door up into the ceiling with such force that you wouldn't be able to hold onto it. If you've ever tried to close a door after you've deployed a slide you'll understand what I'm saying.
None of the above changes if the door has electric assist. As you say the electric motor holds the door back against the counter balance but only if you operate the switch. If you don't operate the switch it will behave like a door that hasn't got the electric assist fitted.
474218 From United States of America, joined Oct 2005, 6340 posts, RR: 10 Reply 9, posted (3 years 6 months 1 week 2 days 14 hours ago) and read 4679 times:
Max777geek From Italy, joined Mar 2007, 538 posts, RR: 0 Reply 10, posted (3 years 6 months 1 week 2 days 7 hours ago) and read 4562 times:
Quoting 474218 (Reply 5): I have no idea what you are trying to say.
The doors have emergency slides which in case of evacuation must be deployed so people can get out of the plane quickly without any other ways to reach the ground. The slide, normally packed, works like an emergency lifeboat and is inflated. When the airplane leave the gate (or the ground ladder goes away) the slide is "armed" it means that is phisically attached to the plane, not sure how this goes on with 767, but on some smaller planes you might have notice a metal bar which is tied to the airplane floor from a door compartment, or on some more moderns liners like airbus, it might be an handle to move, etc. In case the slide is "armed" it does not move anymore with the door, however it gets opened. So rising it manually in the 767 case, will result in much less weight to rise with the door. He ment you can't hold it manually down closed, if just - Ill assume - unlocked, with detached slide. Enough said ?
474218 From United States of America, joined Oct 2005, 6340 posts, RR: 10 Reply 12, posted (3 years 6 months 1 week 1 day 14 hours ago) and read 4346 times:
Quoting Max777geek (Reply 10): The doors have emergency slides which in case of evacuation must be deployed so people can get out of the plane quickly without any other ways to reach the ground. The slide, normally packed, works like an emergency lifeboat and is inflated. When the airplane leave the gate (or the ground ladder goes away) the slide is "armed" it means that is phisically attached to the plane, not sure how this goes on with 767, but on some smaller planes you might have notice a metal bar which is tied to the airplane floor from a door compartment, or on some more moderns liners like airbus, it might be an handle to move, etc. In case the slide is "armed" it does not move anymore with the door, however it gets opened. So rising it manually in the 767 case, will result in much less weight to rise with the door. He ment you can't hold it manually down closed, if just - Ill assume - unlocked, with detached slide. Enough said ?
Now I am really confused now.
Aren't the slide packs on the 767 passenger doors mounted on the doors?
If the slide packs are mounted on the doors they should work as they do on the other aircraft that have doors that open into the cabin overhead. So that: When the door is un-armed and the door is operated the door and slide pack stow in the overhead. However, when the door is shut and armed the girt bar on the bottom of the slide pack attaches to the latch/unlatch mechanism at the door aperture. When the door is opened in an emergency it slides up into the overhead, the girt bar pulls the slide from the door and it deploys as it falls out the door aperture.
Tdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 80 Reply 13, posted (3 years 6 months 1 week 1 day 13 hours ago) and read 4332 times:
Quoting 474218 (Reply 12): Aren't the slide packs on the 767 passenger doors mounted on the doors?
Yes.
The slide is mounted to the bottom of the door. When you arm the door, the girt bar on the slide engages the lower door sill. If you open the door while armed (i.e. the girt bar is engaged) the slide is pulled from it's compartment as soon as the door starts to go up. At that point, the weight of the slide is now sitting on the door sill, so it's weight isn't felt by the door.
If you open the door unarmed (girt bar disengaged), the slide goes up with the door, so the lift system is lifting the door plus the slide.
WNCrew From United States of America, joined Jun 2006, 1317 posts, RR: 9 Reply 14, posted (3 years 6 months 1 week 1 day 12 hours ago) and read 4318 times:
Here's a decent video of a deployment. The 1R cabin door is opened and closed several times DISARMED and then it is ARMED and opened. You can see when it's opened and ARMED the door goes up and since the slide is attached to the door sill the slide pack is pulled out of the pack and falls out and inflates.
474218 From United States of America, joined Oct 2005, 6340 posts, RR: 10 Reply 15, posted (3 years 6 months 1 week 1 day 12 hours ago) and read 4305 times:
MD11Engineer From Germany, joined Oct 2003, 13342 posts, RR: 64 Reply 16, posted (3 years 6 months 1 week 1 day 2 hours ago) and read 4217 times:
Quoting 474218 (Reply 5): Quoting Mender (Reply 4):
If you open a door with the slide armed, the weight of the slide is effectivly detached from the door. Therefore the counterbalance pull the door upwards so strongly that you would not be able to hold it down/closed
I have no idea what you are trying to say. But like I said, in normal operation, when the door is shut electrically it loads the counter balance so the door can be opened in an emergency and deploy the slide. When the door is opened the electric motor actually holds the door back against the counter balance.
Not on the DC-10 / MD-11. There there exists an air motor powered by a reservoir of compressed nitrogen to open the door in emergencies if the normal electric system fails. If the backup system fails as well, you´ll need two strong men to lift up the door manually.
On the 767 there exists a huge spring in the ceiling, which carries the load.